ML20055B151
| ML20055B151 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 07/16/1982 |
| From: | Baynard P FLORIDA POWER CORP. |
| To: | Stolz J Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.B.1, TASK-TM NUDOCS 8207200417 | |
| Download: ML20055B151 (2) | |
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M Power C O m r o a a T e o se July 16,1982
- 3F-0782-14 File: 3-0-26 Mr. John F. Stolz, Chief Operating Reactors Branch #4 Division of Licensing U.S. Nuclear Regulatory Commission Washington, D.C. 20555
Subject:
Crystal River Unit 3 Docket No. 50-302 Operating License No. DPR-72 NUREG-0737, Item II.B.1 Reactor Coolant System Vents
Dear Mr. Stolz:
In the partial response by Florida Power Corporation (FPC) on March 9,1982, of your request for additionalinformation on the above subject dated January 19, 1982, we stated Question 1.a would need further evaluation, and the results of such evaluation would be forwarded to you. Our evaluation is complete, and the results are as follows:
Question 1.
In addition to the operating guidelines for the high point vent system provided as part of your response to NUREG-0737 Item II.B.1, provide additional information regarding the following:
a.
Criteria or pertinent information concerning a decision to terminate venting due to containment hydrogen concentration limits or allowable pressurizer level limits (reference NUREG-0737 Item II.B.1 Clarification A.(2)).
OYb 8207200417 820716 PDR ADOCK 05000 P
General Office 32oi Tnirty-rourth street soutn. P O. Box 14042. Gt Petersburg. Florida 33733 813-866-5151
e Mr. John F. Stolz July 16,1982 Page 2 Response 1.a The reactor coolant system (RCS) hot leg vents are utilized subsequent to an inadequate core cooling incident when cooling has been restored to the core and the RCS is refilling.
This will vent steam / air / hydrogen to the containment atmosphere as the RCS is filled with water. The containment hydrogen purge system is designed to maintain the hydrogen concentration in the containment to less than or equal to 3.5 volume percent (FSAR Section 14 Appendix B). In addition, dedicated penetrations are available for installation of external hydrogen recombiners. As the design concentration is not expected to be reached for several days, time exists for recombiners to be installed. It is not anticipated that this design concentration will be reached as the RCS refill takes ple.ce in a matter of hours while it takes days to generate 3.5 volume percent of hydrogen in the containment, as shown in the FSAR.
If, however, this concentration was being approached because the hot leg vents were venting hydrogen faster than the containment hydrogen purge was releasing it or the recombiners were recombining it, a decision would need to be made as to closing the hot leg vents until the containment hydrogen concentration was reduced and more hydrogen could be allowed in the containment. During this time, the core would be monitored to ensure that it was being adequately cooled. This process would be continued until natural circulation had been established and the RCS was 200F subcooled.
Once natural circulation had been established, the pressurizer vents would be utilized in a similar manner until the pressurizer level reached the appropriate post-accident level.
Very truly yours, b
Dr.P.
. Bay ard Assistant to the Vice President Nuclear Operations RMB:mm cc:
Mr. 3. P. O'Reilly, Regional Administrator Office of Inspection & Enforcement U.S. Nuclear Regulatory Commission 101 Marietta Street N.W., Suite 3100 Atlanta, GA 30303
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